顯示具有 hormone 標籤的文章。 顯示所有文章
顯示具有 hormone 標籤的文章。 顯示所有文章

2008年3月27日 星期四

Hypothalmus

A) Basic concept :

Stimulation -> detection -> regulation -> effector -> correction

* negative feedback mechanism

Stimulate :

a) Directly (hypothalamus act as both detecter and regulator)

  1. Regulation of core temperature
  2. Regulation of plasmic osmolarity
  3. Regulation of hormone level in blood

b) Indirectly (Detected by other organ and regulated by hypothalamus)

- Sensory nerve impulse :

  1. Skin temperature
  2. Sensors in nipples

- Nerve impulses from brain

  1. Smell
  2. Taste

Regulation :

a) Sending nerve impulses to effector :

  1. Skeletal muscle to shrivering
  2. Adrenal gland

b) Secreting hormone :

  1. ADH -> kidney tubules
  2. oxytocin -> milk gland and uterus
  3. FSH -> ovary

c) Secreting trophic hormone :

  1. TSH ----(thyroxid gland)----> thyroxine
  2. releasing factor -> anterior pituitary -> ACTH -> adrenal cortex
  3. LH
  4. FSH

 

B) Major function :

  1. Moniter hormone and other substance level in blood
  2. Regulate body activites, e.G:hunger, sleep
  3. It preduce ADH and oxytocin which then stored in pituitary gland
  4. It control the release of hormone from anterier pituitary by secreting neither inhibiting factor or releasing factor.

The Different and Similarity between Nervous System and Hormonal System

 

Similarity

  1. Cells in both System are capable of transmitting message
  2. Both system are important to coordinate

Difference

Nervous System Hormonal System
-Short term effect -Long term effect
-Faster response -Slower response
-Localized effect -Wildspread effect
-Affect muscle and gland -Affect metabolism and long term process
-electrochemical in nature -chemical in nature